Paper sheet treating device and recorder

ABSTRACT

According to the present invention, a paper sheet managing device is provided. The sheet managing device includes a storage part for storing paper sheets and sheet supply means for supplying a paper sheet from the storage part. The sheet supply means comprises a pick up roller extending in a sheet width direction orthogonal to a sheet feeding direction, a drive shaft extending parallel to the pick up roller and rotationally driving the pick up roller and a plurality of power transmitting means for transmitting a power from the drive shaft to the pick up roller. The plurality of power transmitting means is disposed at at least both ends of the pick up roller and each of the plurality of power transmitting means comprises a gear train that links the drive shaft and the pick up roller and an arm that oscillates the pick up roller. The driving shaft includes processing that prevents rotational phase shifts. With this construction, it is possible to realize a slimline, compact paper sheet managing device that can supply paper reliably using a pick up roller with a long effective length and a small diameter. Using the paper sheet managing device, a slimline and compact printer can be realized.

TECHNICAL FIELD

[0001] The present invention relates to a recording system that printson paper like cut sheets, using a printing mechanism and to a papersheet managing device that is suited to such recording system.

RELATED ART

[0002] In recent years, portable computers such as B5-sized notebookcomputers and pocket-sized computers like PDAs have become widespread.Such computers can connect to the Internet using a mobile phone or PHSphone and obtain a wide variety of information or send and receiveelectronic mail (hereinafter “e-mail”). PHS phones and mobile phonesthat can download various contents and can send and receive e-mail havealso been introduced. Trials are also being undertaken into makingpayments electronically using mobile appliances such as the computersmentioned above or mobile phones.

[0003] Since such mobile appliances are put to various uses in this way,it is extremely important for, users to be able to easily print outinformation including e-mail received by such appliances. For thisreason, there are demands for extremely slimline card-type printers asone accessory for mobile appliances such as mobile phones.

[0004] A slimline card-type printer is more suited to printing onto cutsheets of A6, A7, or A8 size than on a paper roll that is considerablythick. In such printers, a pick up roller is provided to transport thepaper sheets set in the storage part towards a printing head. A bottomplate that is pressed by a pressing spring presses the cut sheets (papersheet) against the pick up roller, so that when the pick up rollerrotates, a suitable frictional force is generated between the roller andthe paper, resulting in a paper sheet being transported towards theprinting head.

[0005] However, there are a number of problems that need to be solved inorder to realize a slimmer printer that is only 5 mm or so thick. First,in order to reduce the thickness of the printer, every component has tobe made more compact, so that in the case of the pick up roller, forexample, the diameter of the roller needs to be set at around 2 mm, eventhough the diameter in a normal printer is around 20 mm. When thediameter of the pick up roller is reduced, the overall structure losesrigidity and becomes flexible, which makes it difficult to maintainprecision. Also, since the overall construction is small, slimlineprinters become more sensitive to minor influences, such as tiny creasesand damage to the paper sheets and changes in the properties of thepaper due to changes in temperature or humidity, that have hitherto notbeen problematic. For these reasons, slimline printers have not beenvery reliable.

[0006] Also, for example, when the diameter of the pick up roller isreduced, the contact area between the roller and the sheet becomessmall. This makes it difficult to produce sufficient force for feedingthe sheet. While it-is possible to maintain a sufficient paper feedingforce by raising the force (pressure) that presses the sheets onto thepick up roller, raising the pressing force would make it even easier forthe pick up roller that lacks rigidity to bend. Raising the pressure istherefore not possible.

[0007] As mentioned above, paper is pressed onto the pick up roller by abottom plate, though to produce a slimline printer, it is difficult toprovide sufficient space for housing the bottom plate and pressingspring and such components should preferably be omitted. However, if thepaper is not pressed onto the pick up roller, a sufficient force cannotbe obtained.

[0008] No matter what mechanism is used for pressing the paper againstthe pick up roller, the low rigidity of the pick up roller means that itis easy for the pick up roller to bend, and even if an improved solutionof the mechanism is found, it is fundamentally still difficult toproduce a sufficient paper feeding force compared to an ordinarymechanism. Accordingly, printers that use a small-diameter pick uproller are sensitive and are therefore easily affected by creases anddamage to the paper and change in the paper quality. In addition, thepaper feeding mechanism needs to be precisely manufactured, with itbeing difficult to maintain such precision for a mechanism havingflexible construction owing to the flexible pick up roller mentionedabove. This means that when there are creases in a paper sheet beingfed, the paper cannot be transported with the correct alignment, whichcan lead to paper feeding errors.

[0009] There is also the problem of motor power. According to aconventional method where sheet is pressed onto the pick up roller,after feeding, a paper sheet is transported by a platen roller, with thepick up roller being rotated by the sheet and becoming a load on theplaten. There are cases where a frictional force acts as an opposingload, so that the motor has the dual loads of rotating the platen androtating the pick up roller. This is to say, the load caused by rotatingthe pick up roller should be unnecessary once a paper sheet has beenfed. Since there are limits on the size of a motor that can be housed ina printer that is around 5 mm thick, increases in the load of the motorthat lead to increases in the size of the motor make it difficult torealize such a slimline printer. Accordingly, it is preferable toeliminate the load of the pick up roller after a paper sheet has beenfed.

[0010] In addition, in a printer that is around 5 mm thick, ifsufficient space is to be provided for storing several dozen sheets, thediameter of the pick up roller is around 2 mm. If a bottom plate is notused and instead the pick up roller is moved so as to press the paperagainst the pick up roller, a mechanism is required for moving the pickup roller over a sufficiently wide stroke in the direction of the paperthickness to reliably pick up every paper sheet right up to the finalsheet, with such mechanism also having to be housed within the slimlineprinter.

[0011] In this way, in order to realize an extremely slimline printerthat is only around 5 mm thick, a number of problems regarding the pickup roller remain to be solved. Accordingly, it is an object of thepresent invention to provide a recording apparatus that solves theseproblems and can reliably feed paper by having suitable contact made bythe pick up roller and the paper sheet. It is another object of thepresent invention to provide an extremely slimline recording system,such as an apparatus that is around 5 mm thick, that can be used as anaccessory of a mobile appliance, such as a mobile phone. It is yetanother object of the present invention to provide a recording systemwith high print quality in spite of being slimline and compact.

DISCLOSURE OF THE INVENTION

[0012] According to the present invention, a paper sheet managing deviceis provided. The sheet managing device includes a storage part forstoring paper sheets and sheet supply means for supplying a paper sheetfrom the storage part. The sheet supply means comprises a pick up rollerextending in a sheet width direction orthogonal to a sheet feedingdirection, a drive shaft extending parallel to the pick up roller androtationally driving the pick up roller and a plurality of powertransmitting means for transmitting a power from the drive shaft to thepick up roller. The plurality of power transmitting means is disposed atat least both ends of the pick up roller and each of the plurality ofpower transmitting means comprises a gear train that links the driveshaft and the pick up roller and an arm that oscillates the pick uproller. The arm swings about an axis of a gear in the gear train, to afront end of the arm, a rotational axis of the pick up roller isattached so as to a plurality of gears that form at least part of thegear train (wheel train) links between the axis about which the armswings and the rotational axis of the pick up roller. In addition, thearm includes frictional load generating means that has frictiongenerated in accordance with rotation between the arm and either theeven number of gears or the rotational axis of the pick up roller. Anirregularly shaped shaft type, such as a part cut in a D shape type, isapplied at engaging parts of the driving shaft and the pick up rollerthat are engaged to the gears so as to prevent shifts in rotationalphase.

[0013] The present invention also provides a recording system includinga print head, sheet feed means for feeding paper sheet under controllinga feeding speed for printing by the print head, and the paper sheetmanaging device described above.

[0014] With the paper sheet managing device of the present invention,when the drive shaft rotates, the pick up roller is rotated via the geartrains of the power transmitting means in a suitable direction for thesheet feeding direction, and the pick up roller is swung so as tocontact the paper by the frictional force generating means provided atthe ends of the arms that support the pick up roller. When the pick uproller contacts the paper and a sheet feeding force is produced, areactionary force presses the pick up roller onto the paper since thepick up roller is supported by the arms. This means that the pick uproller is pressed onto the paper by the power transmitting means,thereby producing the required frictional force for feeding the paperbetween the pick up roller and the sheet, so that paper sheet can be fedto the print head without using a bottom plate or a pressing spring.

[0015] In addition, with the sheet supply means or method where the pickup roller is driven by power transmitting means having arm, the pick uproller is moved in the thickness direction of the sheet, which makes iteasy to achieve a sufficient stroke in the thickness direction.Accordingly, even though no bottom plate is used, sheets can be reliablyfed to the final sheet using a pick up roller with a small diameter. Toincrease the stroke, it is preferable for the driving gear that isconnected to the drive shaft and the driven gear that is connected tothe pick up roller not to be directly linked and for one or a pluralityof intermediate gears to be used to link these gears. By providing oneor more intermediate gears, the swing radius of the rotational axis ofthe pick up roller can be increased without increasing the diameters ofthe driving gear and the driven gear.

[0016] If the power transmitting means are disposed on the outside ofthe storage part, the diameter of the intermediate gear can be increasedwithout making the storage part thicker or sacrificing the space forstoring paper. Accordingly, a large stroke can be achieved by attachingthe arms so as to swing about rotational axes of the intermediate gears.In this case, the intermediate gear and driven gear correspond to theeven number of gears that link the center about which the arms swing andthe rotational axis of the pick up roller. On the other hand, when thepower transmitting means are disposed on the inside of the storage part,increasing the diameter of the intermediate gears results in a decreasein the space in the storage part. However, by having the arms swingabout the rotational axis of the driving gear, which is to say, aboutthe drive shaft, a large stroke can be achieved without sacrificing thespace of the storage part by providing an even number of intermediategears, whose diameters are equal to or less than the diameter of thedriven gear, on the arms.

[0017] In addition, with a sheet supply means or method where the pickup roller is driven by power transmitting means including arms, afterpaper has been fed by the pick up roller, the pick up roller can beprevented from acting as a load when the paper is transported by a sheetfeed means such as a platen roller that is located close to the printhead. By setting a sheet feeding speed of the sheet feed means higherthan a sheet feeding speed of the sheet supply means, that is the sheetfeeding speed of the pick up roller, a sheet feeding force of the pickup roller is not applied onto the paper. As a result, no reactionaryforce acts so as to press the pick up roller onto the paper and nopressuring force is applied onto the paper by the pick up roller, sothat the pick up roller freewheels. This means that once the paper hasbeen fed, the pick up roller does not provide resistance or load whenthe paper is being transported by the sheet feed means. The load of thesheet feeding means for feeding paper is reduced, so that the motordriving force can be reduced, thereby making it possible to transportpaper with an extremely small motor. The thickness of an extremelyslimline recording apparatus that includes a motor can therefore besuppressed to around 5 mm.

[0018] In this way, using power transmitting means that include arms forsupporting the pick up rollers of the sheet feed means solves a numberof the aforementioned problems relating to the realization of anextremely slimline paper sheet managing device and recording apparatusor system. In addition, according to the present invention, sufficientforce for feeding paper can be produced with a pick up roller with asmall diameter (i.e., low contact area) and low rigidity (i.e.,flexibility) by increasing the contact area by having the pick up rollercome into contact with at least 50% of the paper sheet width. Also,bending is prevented by supporting at least both ends of the pick uproller with the power transmitting means, with the drive shaft beingprovided parallel to the pick up roller so that the power transmittingmeans can be disposed at both ends of the pick up roller.

[0019] In addition, by using a long pick up roller with a small diameterthat is driven at both ends, since the pick up roller itself lacksrigidity, should the rotation of the drive shaft by the powertransmitting means at ends move out of synchronization, there will bevariations in the sheet feeding force at ends that can cause deviationin the sheet feeding direction and in the pick up roller bending. Forthis reason, the present invention uses a method where the rotationalphase between the drive shaft and the pick up roller is strictlymaintained, so that the rotational force compensates the flexibleconstruction, thereby raising the precision. This is to say, irregularlyshaped type shafts that are not circular and are D-shaped incross-section, for example, are provided at parts where the gear trainsof the power transmitting means engage the pick up roller and the driveshaft, so that shifts of the rotational phase of all of the gears arestrictly prevented. Also, since the plurality of power transmittingmeans operate with the same phase in any case, even if there are creasesin the paper sheet, the paper is squeezed between the pick up roller andthe base surface of the storage part, thereby straightening thesecreases and making it possible to feed the sheet towards the printmechanism with the correct orientation without being affected by suchcreases.

[0020] Accordingly, with the paper sheet managing device of the presentinvention, the pick up roller is elongated and is supported at at leastboth ends by power transmitting means equipped with arms, so that abottom plate can be omitted, a sufficient paper feeding force forfeeding paper with the appropriate orientation can be ensured byextending the contact width of the pick up roller that is flexible dueto its small diameter, a sufficient stroke can be ensured in the paperthickness direction, and the pick up roller can be prevented frombecoming a load when paper is being transported by a sheet feed meanssuch as a platen roller. Therefore, by using a pick up roller with anextremely small diameter of around 2 mm, sufficient space for storingpaper can be provided in a slimline paper sheet managing device that isaround 5 mm thick, with it being possible to pick up and supply everysheet right up to the final sheet without paper jams occurring.Accordingly, with the present invention, it is possible to provide apaper sheet managing device that is extremely slim overall but canreliably supply paper. This makes it possible to provide a recordingsystem that can be used as an accessory of a mobile appliance such as amobile phone or can be incorporated into a mobile appliance, with theoverall construction being extremely slim and print quality being high.

[0021] By providing a shaft bearing that supports the drive shaft at anintermediate position aside from or in addition to both ends of thedrive shaft, which is to say, at at least one position inside thestorage part, a drive shaft with a small diameter can be prevented frombending. In addition, the power transmitting means that also support thepick up roller may be provided at one or more positions in theintermediate position of the pick up roller aside from or in addition toboth ends of the pick up roller, thereby preventing bending and warpingin the pick up roller and making it easy to apply pressure.

[0022] The present invention includes a paper sheet managing device andrecording system where a plurality of sheets of paper can be setdirectly or using a sheet cassette that stores a plurality of sheets ofpaper, in the storage parts. In particular, by using a storage part witha size or form whereby a tongue-like underlay that protrudes from acassette is positioned opposite the pick up roller, it becomes possibleto use a sheet cassette with a protruding underlay, so that every sheetof paper can be picked up with the same conditions right up to the finalsheet. This means it is possible to provide a paper sheet managingdevice where every sheet can be reliably fed right up to the finalsheet.

[0023] Since the paper sheet managing device of the present invention isextremely slim, a plurality of storage parts can be stacked on multiplelevels so as to feed different types or sizes of sheets. This is to say,the present invention also includes a paper sheet managing device and arecording system that have a plurality of storage parts and a pluralityof sheet supply means that respectively supply sheet from such storageparts. In particular, a paper storing apparatus of the present inventionis suited to a multi-tray where a plurality of storage parts are stackedon multiple levels.

BRIEF DESCRIPTION OF THE DRAWINGS

[0024]FIG. 1 is cross-sectional views showing the overall constructionof a printer according to the present invention.

[0025]FIG. 2 is a perspective view showing a paper sheet managing deviceof the printer of the present embodiment, and shows the state before apaper cartridge has been set in the storage part of the paper sheetmanaging device.

[0026]FIG. 3 is a perspective view showing the state once a papercartridge has been set in the storage part of the paper sheet managingdevice.

[0027]FIG. 4(a) is a cross-sectional view showing the overallconstruction of the power transmitting mechanisms in the presentembodiment, and FIG. 4(b) is a planar view of the same.

[0028]FIG. 5 shows the operation of the power transmitting mechanisms ofthe present embodiment and the movement of the pick up roller.

[0029]FIG. 6 is a perspective view showing a different example of thepaper sheet managing device.

[0030]FIG. 7(a) is a perspective view showing yet another example of thepaper sheet managing device, while FIG. 7(b) is a perspective viewshowing an enlargement of the periphery of the pick up roller of suchpaper sheet managing device.

[0031] FIG; 8 shows an example of a paper sheet managing device in whicha plurality of storage parts are stacked on multiple levels.

BEST MODE FOR CARRYING OUT THE PRESENT INVENTION

[0032] The following describes several embodiments of the presentinvention with reference to the enclosed drawings. FIGS. 1(a) and 1 (b)are cross-sectional figures showing the overall construction of aprinter 1 according to the present invention. The printer 1 of thepresent embodiment has a slimline or thin rectangular housing 5 with anoverall size of around A7 size (74 mm by 105 mm) and is around 5 mmthick, making it extremely suited to use as a portable printer. A rearend part 1 b of the housing 5 is a paper sheet managing compartmentwhere a plurality of A8 (52 mm by 74 mm) size thermosensitive cut sheets3 (thermal sheets or thermal paper) can be stored, and from the sheetstored, one sheet is picked up and fed at a time. Therefore, thatcompartment is a “paper sheet managing part” or a “paper sheet managingdevice” 2. A front end part 1 a is a compartment in which a printingmechanism 4 for printing the thermal sheet 3 fed from the paper sheetmanaging part 2 is disposed. The printing mechanism 4 includes a thermalhead 6 that prints on the thermal sheet 3, and a platen roller 7 thattransports the thermal sheet 3 while pressing the thermal sheet 3 ontothe thermal head 6. Accordingly, the paper 3 fed from the paper sheetmanaging part 2 passes between the thermal head 6 and the platen roller7 with the platen roller 7 as a sheet feed means, is printed upon, andis discharged to the outside from a discharge slot 8 provided in thefront end 1 a.

[0033]FIG. 2 and FIG. 3 are perspective views that show the overallconstruction of the paper sheet managing device 2 included in theprinter 1. This paper sheet managing device 2 is a sheet storingapparatus or sheet supplying apparatus that holds sheets for the printer1 and supplies sheets according to orders from the printer 1. FIG. 2shows the paper sheet managing device 2 in a state before a sheetcassette has been set and FIG. 3 shows the paper sheet managing device 2in a state after a sheet cassette has been set. The paper sheet managingdevice 2 includes a storage part 15 that stores the thermal sheets 3 anda sheet supply means 19 that picks up paper sheet stored in the storagepart 15 and supplies the paper one sheet at a time. In the printer 1,the housing 5 and the paper sheet managing device 2 are integrallyprovided, with part of the housing 5 constructing a base 11 of thestorage part 15, which supports the thermal sheets 3, and an upper case12, which covers the storage part 15, so as to protect the thermalsheets 3 from the outside environment. In addition, side walls 17 and 18extend upwards from the base 11. These side walls 17 and 18 support themechanism that serves as the sheet supply means 19 and surround theinternal space that serves as the storage part 15. In addition, a guideprotrusion 41 is formed on the base 11 in the storage part 15 so that apaper sheet cartridge (paper sheet cassette) 9, which stores a pluralityof A8-sized (52 mm by 74 mm) thermal sheets 3, can be set in apredetermined state at a predetermined position from the rear end 1 b.

[0034] The sheet supply means 19 of the paper sheet managing device 2includes a pick up roller 21 that extends from the side wall 17 to theside wall 18, a drive shaft 22 that is disposed parallel to the pick uproller 21, and power transmitting mechanisms 42 a and 42 b that aredisposed on the outside of the lo side walls 17 and 18. The pick uproller 21 is disposed on the paper feeding side, which is on theprinting mechanism 4 side of the storage part 15, and extends in a sheetwidth or lateral direction W that is perpendicular to or orthogonal tothe sheet feeding direction P. When a sheet cassette 9 has been set inthe storage part 15, the pick up roller 21 contacts the uppermostthermal sheet 3 that is 15 exposed at an opening 9 a of the sheetcassette 9. With the sheet cassette 9 of the present embodiment, atongue-like member 9 b extends from a main body 9 c at a front end 9 dso as to serve as an underlay for the opening 9 a, with the final fewthermal sheets 3 being held between the pick up roller 21 and thetongue-like member 9 b and fed. In particular, the final thermal sheet 3is set so as to slide on the tongue-like member 9 b that is made ofpaper or has a similar frictional coefficient as paper, so that theconditions for frictional coefficient around the final sheet is the sameas for the other sheets. This means that the sheet 3 can be reliably fedright up to the final sheet without the final sheet being fed togetherwith the sheet above it or the final sheet failing to be picked up.

[0035] The pick up roller 21 of the present embodiment has a smalldiameter so that it can be housed in the slimline printer 1, and forexample can be an extremely fine roller with a diameter of around 2 mm.When a thermal sheet 3 that is contacted by the pick up roller 21strikes a front wall 16 of the storage part 15 due to the rotation ofthe pick up roller 21, only the very top thermal sheet 3 is separatedand is fed at a sheet feeding speed S2, which is proportionate to therotational speed of the pick up roller 21, towards the printingmechanism 4 positioned at the front end part 1 a. When the front end ofthis thermal sheet 3 becomes held between the platen roller 7 and thethermal head 6, the thermal sheet 3 receives a driving force from theplaten roller 7 and is transported at a sheet feeding speed S1, which isproportionate to the rotational speed of the platen roller 7, with adesired printing operation being performed by the thermal head 6.

[0036] The drive shaft 22 extends in the sheet width direction Wparallel with the pick up roller 21, is a member for transmitting arotational driving force to the pick up roller 21, and is driven by amotor (not shown in the drawing) via a suitable gear mechanism. Adriving force is transmitted from the drive shaft 22 to both ends of thepick up roller 21 via the power transmitting mechanisms 42 a and 42 b,so that the pick up roller 21 rotates. In the present embodiment, thetwo power transmitting mechanisms 42 a and 42 b are both positioned onthe outside of the side walls 17 and 18, which is outside the storagepart 15, so that the power transmitting mechanisms 42 a and 42 b can bepositioned without taking up space in the storage part 15. The powertransmitting mechanisms 42 a and 42 b have the same construction andexhibit right/left symmetry, so that only the power transmittingmechanism 42 a is described below as a representative example of thetwo.

[0037] FIGS. 4(a) and 4(b) are a cross-sectional view and a sideelevation showing the construction of the power transmitting mechanism42 a in more detail. As shown in FIGS. 2 to 4, the power transmittingmechanism 42 a is disposed at one end 21 e of a shaft 21 a of the pickup roller 21, and includes a gear train (wheel train) 25 that links thedrive shaft 22 and the pick up roller 21, an arm 30 that swings the pickup roller 21, and felt 45 as a frictional force generating means forgenerating a frictional force between the arm 30 and axis 21 a of thepick up roller 21 when the pick up roller 21 rotates.

[0038] The gear train 25 includes a driving gear 27 that is linked toand driven by the drive shaft 22, a passive or driven gear 28 that islinked to the roller shaft 21 a of the pick up roller 21 and drives thepick up roller 21, and a single intermediate gear 29 that links thedriving gear 27 and the driven gear 28. The drive shaft 22 and theroller shaft 21 a of the pick up roller 21 both pass through the sidewalls 17 and 18 of the base 11 and protrude to the outside of thestorage part 15, with the protruding parts 46 and 47 being fixed to thegears 27 and 28 respectively. On the other hand, the intermediate gear29 rotates about a shaft and axis 32 that is attached to the first sidewall 17, with one end 30 a of the arm 30 being attached to this shaft 32so that the arm 30 is able to swing around the axis 32.

[0039] Accordingly, the arm 30 swings about the shaft and axis 32 of theintermediate gear 29 that forms part of the gear train 25. The other end30 b of the arm 30 is attached to the roller shaft and axis 21 a of thepick up roller 21. As a result, in the printer 1 of the presentembodiment, the axis 32 of the arm 30 and the rotational axis 21 a ofthe pick up roller 21 are linked by two gears (i.e., an even number ofgears), which are the intermediate gear 29 and the driven gear 28. Apart 46 of the drive shaft 22 where the driving gear 27 is attached(i.e. a gear-engaging part of the drive shaft 22) and a part 47 of theshaft 21 a of the pick up roller where the driven gear 28 is attached(i.e. a gear-engaging part of the pick up roller 21) are irregularly orcomplementally shaped shaft parts that have been cut in D-shapes asshown in FIG. 4(b). This means that these gears 27 and 28 can berespectively fixed to the shafts 22 and 21 a without slipping, whichcompletely prevents rotational phase shifts of the gears 27 and 28 atthese parts 46 and 47, so that these parts 46 and 47 make it possible tomove the gears with precise synchronization.

[0040] As shown in FIG. 4(a), felt 45 that generates a suitablefrictional force when the pick up roller 21 rotates is provided inbetween the driven gear 28 and the arm 30 at the end 30 b of the arm 30that supports the pick up roller 21. This means that the rotationalforce of the pick up roller 21 is used as a force for swinging the arm30 about the axis 32. The arm 30 is swung by the rotation of the pick uproller 21 so that the pick up roller 21 too can be swung. In the presentembodiment, in view of the thickness of the storage part 15, a curvedguide channel 35 is formed in the side walls 17 and 18 so that the pickup roller 21 can swing through a predetermined stroke in this thicknessdirection.

[0041] FIGS. 5 show how a thermal sheet 3 is supplied by driving thepick up roller 21 via the power transmitting mechanism 42 a of thepresent example. As shown in FIGS. 5(a) and 5(b), when the drive shaft22 is driven in the clockwise direction, the driving gear 27 rotates inthe clockwise direction, the intermediate gear 29 rotates in theanticlockwise direction, and the driven gear 28 rotates in the clockwisedirection. The felt 45 that generates a frictional force is held betweenthe driven gear 28 and the arm 30, so that a force Y that swings thepick up roller end 30 b of the arm 30 in the anticlockwise direction isgenerated. The other end 30 a of the arm 30 that is attached to commonaxis 32 with the intermediate gear 29 to pivot in the anticlockwisedirection around the axis 32. Accordingly, the pick up roller end 30 bof the arm 30 rotates in the anticlockwise direction, which moves thepick up roller 21 in the direction of the thermal sheets 3.

[0042] When the pick up roller 21 comes into contact with the thermalsheets 3, the pick up roller 21 is rotationally driven in the clockwisedirection, so that a force X acts so as to feed the thermal sheet 3 withwhich the pick up roller 21 is in contact in the sheet feeding directionP. On the other hand, a reactionary force Z to the force X acts on thepick up roller 21 itself. The pick up roller 21 is supported by the arm30 so as to be able to swing about the axis 32, so that the reactionaryforce Z acts so as to further rotate the arm 30 in the anticlockwisedirection and as a result a force F that presses the pick up roller 21in the direction of the thermal sheets 3 is produced. In the sheetsupply means 19 of the present example, when the drive shaft 22 isdriven by a motor, the pick up roller 21 rotates in the sheet feedingdirection and the arm 30 moves in a direction that presses the pick uproller 21 onto the thermal sheets 3. When the feeding of a paper sheetcommences by the pick up roller 21, the reactionary force acts so as topull the pick up roller 21 onto the thermal sheets 3. As a result, thepick up roller 21 can be strongly pressed onto the thermal sheets 3, anda sufficient frictional force for feeding a paper sheet is producedbetween the pick up roller 21 and the thermal sheet 3. Accordingly, inthe printer 1 of the present embodiment, a force that presses the pickup roller 21 itself onto the thermal sheets 3 acts as a reaction to therotational movement of the pick up roller 21, so that the pick up roller21 can reliably feed thermal sheets 3 towards the printing mechanism 4even if no bottom plate or pressing plate is used.

[0043] Also, as shown in FIGS. 5(c) and 5(d), in the printer 1, even ifthere are only a few thermal sheets 3 left, the rotation of the pick uproller 21 results in the pick up roller end 30 b of the arm 30 beingrotated in the direction of the thermal sheets 3 by the frictional loadgenerating means 45 that uses the felt, so that the pick up roller 21comes into contact with the thermal sheets 3. When the pick up roller 21comes into contact with the thermal sheets 3 and the force X that movesa thermal sheet 3 is generated, the reactionary force Z to this force Xpresses the pick up roller 21 against the thermal sheets 3 as describedabove. This means that the thermal sheets 3 are always pressed with asuitable force by the roller 21. As a result, regardless of the numberof cut sheets 3 that are held in the sheet cassette 9, the pick uproller 21 can always press the thermal sheets 3 so as to produce therequired frictional force for feeding sheets, and the cut sheets 3 canalways be fed towards the printing mechanism 4.

[0044] In this way, with the sheet supply means 19 of the presentembodiment, the pick up roller 21 is supported by the power transmittingmechanisms 42 a and 42 b, which include the arms 30 and transmit thedriving force to the pick up roller 21, so that the pick up roller 21can be reliably pressed onto the thermal sheets 3 without using a bottomplate or a pressing spring. Accordingly, no space is required forhousing a bottom plate or a pressing spring, so that the approximately 5mm thickness of the housing 5 of the extremely slimline printer 1 can beeffectively used for storing the thermal sheets 3. In addition, byrotating the pick up roller 21, the arms 30 are pivoted in the directionof the paper, so that every thermal sheet 3 rights up to the final sheetcan be reliably picked up.

[0045] In the present embodiment, the power transmitting mechanisms 42 aand 42 b are disposed on the outside of the storage part 15, so thatintermediate gears 29 with a large diameter can be used withoutsacrificing the internal storage space of the storage part 15.Accordingly, a distance can be provided between the drive shaft 22 andthe pick up roller 21, making it possible to attach arms 30 that have alarge rotational radius and can move through a large stroke in thethickness direction of the storage part 15. This means that an extremelyfine pick up roller 21 with a diameter of around 2 mm can be used andaround 3 mm in a printer 1 with a thickness of around 5 mm can be set asthe storage space 15 for the thermal sheets 3, which makes it possibleto hold several dozen sheets, with it also being possible to reliablyfeed every thermal sheet 3 right up to the final sheet held in thestorage space 15.

[0046] In addition, the paper storage part 15 has a suitable size forstoring the thermal sheets 3 in the sheet cassette 9 whose tongue-likemember 9 b extends or protrudes outward in the sheet feeding direction.This means that by setting the sheet cassette 9 that as described abovehas the tongue-like member 9 b with a similar frictional coefficient asthe sheet, it is further ensured that every thermal sheet 3 right up tothe final sheet can be effectively used.

[0047] The power transmitting mechanisms 42 a and 42 b that use the arms30 transmit the driving force to the pick up roller 21, and thereactionary force Z to the paper feeding force X of the pick up roller21 is used to obtain the pressing force F that presses the pick uproller 21 on the thermal sheets 3, thereby producing the frictionalforce required to feed the sheets. This means that when the sheetfeeding force X is not present, there is no reactionary force Z andconsequently no pressing force F. If the sheet feeding speed S1 of theplaten roller 7 that is the sheet feed means of the printer 1 is setfaster than the sheet feeding speed S2 of the paper sheet managingdevice 2, the thermal sheet 3 that is pulled by the platen roller 7 isnot subjected to the sheet feeding force X, so that there is noreactionary force Z and consequently no pressing force F. Accordingly,in the paper sheet managing device 2 of the present embodiment, as shownin FIG. 1(b) when the thermal sheet 3 that has been supplied by the pickup roller 21 is transported or fed by the platen roller 7, the pick uproller 21 freewheels on the surface of the thermal sheet 3 and so hardlyproduces any friction. This means that when a thermal sheet 3 istransported by the platen roller 7, the thermal sheet 3 is not pulled bythe pick up roller 21, so that it is possible to substantially orentirely prevent a load from being created by the pick up roller 21 whena thermal sheet 3 is being transported by the platen roller 7. Usingthis paper sheet managing device 2 therefore makes it possible to reducethe paper transportation load of the platen roller 7, so that comparedto conventional apparatuses, a motor with less torque can be used as thedriving motor.

[0048] A motor that generates low torque is compact, which makes itpossible to house a motor with a suitable size in an extremely slimlineprinter 1 such as that of the present embodiment whose thickness isaround 5 mm. By reducing the torque, it is also possible to reduce thepower consumption of the motor. When a battery is included in theprinter 1, the battery can also be miniaturized, so that a printer thatincludes a battery can also be compactly produced. Alternatively, alarge increase can be made in battery life, which makes it possible toprovide a printer that is highly suited to mobile use.

[0049] With the printer 1 of the present example, the force F thatpresses the pick up roller 21 on a cut sheet 3 can be suppressed whenthe cut sheet 3 is being transported by the platen roller 7, so thatproblems such as the surface of the cut sheet 3 becoming shiny (“sheen”)can be avoided. This phenomenon occurs when a thermal sheet 3 is pulledfaster than the sheet feeding speed of the pick up roller 21 with thepick up roller 21 continuously applying pressure to the thermal sheet 3.On the other hand, in the printer 1, when the thermal sheet 3 is pulledfaster than the sheet feeding speed of the pick up roller 21, nopressing force F is generated, thereby suppressing the above phenomenon.This means that it is possible to provide a printer capable of highquality print output using the thermal sheets 3.

[0050] In this way, with the sheet supply means 19 of the presentexample in which the pick up roller 21 is supported by the arms 30,enough space for storing sheets can be provided in a slimline space,every sheet right up to the final sheet can be reliably fed, and themotor can be miniaturized, which makes this sheet supply means 19 verysuited to a slimline printer 1. The contact part is elongated in thesheet width direction W, which increases the contact area and makes itpossible to produce sufficient force for feeding paper even with a smallpick up roller 21. In addition, both ends 21 e of the pick up roller 21are supported by the power transmitting mechanisms 42 a and 42 b whichprevents bending and warping, so that the pick up roller 21 can be madean extremely fine with a diameter of around 2 mm.

[0051] This is to say, as shown in FIGS. 2 and 3, the pick up roller 21extends almost completely across the sheet width direction W of the cutsheets 3, so that the pick up roller 21 contacts the entire sheet widthof the cut sheets 3. Accordingly, a pick up roller 21 with a smalldiameter has a sufficient contact surface area with the thermal sheet 3,and the desired sheet feeding force can be obtained without pressing thepick up roller 21 against the thermal sheet 3 with such a strongpressing force. The pressing force of the pick up roller 21 cantherefore be minimized so as to suppress the bending and warping of thesmall-diameter pick up roller 21, with a sufficient paper feeding forcestill being produced.

[0052] By ensuring that there is sufficient area for contact in thesheet width direction W, it is easy to apply force evenly to the entirethermal sheet 3. This means that it is possible to feed the thermalsheet 3 correctly in the predetermined sheet feeding direction P, andthat paper jams where the sheet feeding direction W of the thermal sheet3 is skewed can be prevented. In particular, in a slimline printer 1,there is very little space for the sheet feeding path, etc., so that itis important to feed paper sheet with the correct orientation. Extendingthe effective length of the pick up roller 21 is also effective infeeding paper sheets correctly. Also, a pick up roller 21 with a smalldiameter like in the present example has flexible structure, and so caneasily become bent or warped due to factors such as small undulations inthe thermal sheet 3. By increasing the length of the pick up roller 21that contacts the thermal sheets 3, even if there is some deformation inthe pick up roller 21 that results in some parts coming intoinsufficient contact with the thermal sheets 3, the effect of such partsis minimized, so that thermal sheets 3 can be fed with high reliability.

[0053] In a conventional printer, the diameter of the pick up roller isaround 20 mm or is even larger, which makes the pick up roller extremelyrigid and makes it possible to apply a strong pressing force on the pickup roller. This means that the length of the pick up roller thatcontacts the sheets may be reduced. Conversely, when this length isincreased, there are cases where the sheet feeding direction becomesskewed due to phase shifts such as those described later. However, withthe printer 1 of the present embodiment, the pick up roller 21 isextremely slim with a diameter of around 2 mm, so that the above kind ofdesign cannot be used. By increasing the contact area, the pick uproller 21 is lengthened and a sheet feeding force is produced evenlyacross the entire width of the pick up roller 21, so that the thermalsheets 3 can be fed with the correct orientation even if there is acertain degree of curved, creased in the sheets. This means that it ispreferable for the effective length of the pick up roller 21 to be long,and by using a design where the pick up roller 21 comes into contactwith at least 50% of the width of the sheet, the thermal sheets 3 can befed with sufficient force so as to prevent the sheets from becomingskewed.

[0054] By using this kind of long pick up roller 21 with a smalldiameter, thermal sheets 3 can be reliably fed even in a slimlineprinter 1 that is around 5 mm thick, though to obtain a sufficient paperfeeding force, a certain amount of force has to be applied onto the pickup roller 21, which means that a long, flexible pick up roller 21 with asmall diameter of around 2 mm is susceptible to the effects ofdeformations such as bending, warping, and twisting. When the pick uproller 21 deforms, the long effective length makes it easy for the pickup roller 21 to withstand sheet feeding effect due to the deformation,though such deformation reduces the reliability of paper-feedingoperations.

[0055] With the sheet supply means 19, the bottom plate is omitted tosave space as described above and the sheet supply means 19 isconstructed so that the pick up roller 21 is swung through asufficiently long stroke by the arms 30. This means that the pick uproller 21 cannot be attached directly to the side walls 17 and 18. Forthis reason, the power transmitting mechanisms 42 a and 42 b thatinclude the arms 30 support both ends 21 e of the pick up roller 21, andthe pick up roller 21 is driven at both ends 21 e simultaneously. Inaddition, to reliably drive the pick up roller 21 with both ends insynchronization, a drive shaft 22 that can apply a common driving forceto both ends 21 e is disposed parallel to the pick up roller 21, theengagement of the gears in the power transmitting mechanisms 42 a and 42b are used, and for preventing the rotational phase shift, theirregularly shaped shaft parts 46 and 47 cut into D shapes are providedat the parts of the drive shaft 22 and the pick up roller 21 that engagethe driving gear 27 and the driven gear 28 respectively. Accordingly,when the drive shaft 22 is driven, even if the sheet feeding directionmay be easy changed by commencing the sheet feeding or by existingcreases, both ends 21 e of the pick up roller 21 can be driven withoutphase shifts, so that twisting and warping of the pick up roller 21 canbe avoided, which makes it possible to reliably supply the paper in thepredetermined direction. In addition, by supporting the pick up roller21 at both ends 21 e, bending and warping in the pick up roller 21 areprevented while using a structure where the roller can be swung by thearms 30. This means that a reliable paper feeding force can be obtained,and that the sheet feeding direction can be properly maintained.

[0056] In this way, the power transmitting mechanisms 42 a and 42 b thatinclude the arms 30 both support the extremely long and flexible pick uproller 21 and transmit the rotational force, so that the thermal sheets3 can be pressed with a sufficient force without bending the pick uproller 21, and a thermal sheet 3 can be reliably fed to the printingmechanism 4 with the proper orientation. This means that asmall-diameter pick up roller can be used and a bottom plate andpressing spring can be omitted, which makes it easier to reduce thethickness of a printer and makes it possible to hold a sufficient numberof sheets 3 even in a slimline printer. Accordingly, the printer 1 ofthe present example makes it possible to realize an extremely slimlinecard-type printer whose entire body is around 5 mm thick or is evenslimmer. Such a printer can be incorporated in or attached to a mobileappliance such as a mobile phone, so that it is possible to provide anextremely small printer that can be carried together with a mobileappliance.

[0057] The printer 1 described above is provided with the intermediategear 29 that is provided in the gear train 25 of the power transmittingmechanisms 42 a and 42 b, with the arms 30 swinging through a wide rangeand the range of movement (stroke) of the pick up roller 21 in thethickness direction also being wide. To prevent the large-diameterintermediate gears 29 from taking up space in the storage part 15, thepower transmitting mechanisms 42 a and 42 b are provided on the outsideof the storage part 15, and in the present example, on the outsides ofthe side walls 17 and 18. Accordingly, a large stroke can be ensured,though the roller shaft 21 a of the pick up roller 21 needs to extendbeyond the width of the thermal sheets 3 to the outsides of the sidewalls 17 and 18. Since the span becomes wide, this makes the pick uproller 21 susceptible to bending. On the other hand, it is also possibleto provide the power transmitting mechanisms 42 a and 42 b close to thestorage part 15 or even inside the storage part 15. An example of such apaper sheet managing device 2 is shown in FIG. 6.

[0058] In the paper sheet managing device 2 shown in FIG. 6 also, bothends 21 a of the pick up roller 21 are supported by power transmittingmechanisms 43 a and 43 b that include the arms 30. However, the geartrains 25 of the power transmitting mechanisms 43 a and 43 b in thisexample are composed of driving gears 27 that are connected to the driveshaft 22 and driven gears 28 that are connected to the pick up roller21, with these gears 27 and 28 engaging one another directly. The arms30 swing about the center of rotation of the driving gears 27, which isthe drive shaft 22, with both ends 21 e of the pick up roller 21 beingsupported by the arms 30 so that the pick up roller 21 can be swungabout the drive shaft 22. Accordingly, two gears (an even number ofgears), which are the driving gear 27 and the driven gear 28, link ashaft 32 about which the arms 30 swing and the rotational axis 21 a ofthe pick up roller 21.

[0059] The power transmitting mechanisms 43 a and 43 b of the presentexample are also equipped with a frictional force generating means, suchas felt, between the driven gears 28 and the pick up roller-side of thearms 30, so that when the pick up roller 21 is driven, the same actionis produced as with the power transmitting mechanisms 42 a and 42 bdescribed above. This is to say, when looking at the power transmittingmechanism 43 a from the side, when the drive shaft 22 is rotationallydriven in the anticlockwise direction, the pick up roller 21 is rotatedin a clockwise direction, which is the sheet feeding direction, by thegear train 25 of the power transmitting mechanism 43 a. When the pick uproller 21 rotates in the clockwise direction, a moment that swings thepick up roller-side of the arm 30 in the anticlockwise direction isgenerated. With the power transmitting mechanism 43 a of the printer 1of the present example, the drive shaft 22, which is the center ofrotation of the arms 30, also rotates in the anticlockwise direction inwhich the arms 30 swing, so that the moment that is generated by thefrictional load generating means swings the arms 30 in the directionthat has the pick up roller 21 contact the thermal sheets 3. When thepick up roller 21 has come into contact with the thermal sheets 3 andgenerated a sheet feeding force, the reaction to this force furtherpresses the pick up roller 21 against the thermal sheets 3, so that astable force is generated. The same operation also happens in the powertransmitting mechanism 43 b on the opposite

[0060] In the sheet supply means 19 of the paper sheet managing device2, by disposing the power transmitting mechanisms 43 a and 43 b insidethe storage part 15, the overall length of the pick up roller 21 isreduced while maintaining the effective length of the pick up roller 21that contacts the thermal sheets 3. Accordingly, this construction canreduce the amount of bending in the pick up roller 21, and since thepower transmitting mechanisms do not need to be disposed on the outsidesof the side walls 17 and 18, the constructions at the sides can besimplified. This means that the paper sheet managing device 2 cantherefore be made more compact, making it even more suited to a compactslimline printer. With this construction too, irregularly shaped partsthat are not circular, such as D-shaped parts or square parts are formedin the drive shaft 22 and the shaft 21 a of the pick up roller so as tostop the gears from slipping and reliably synchronize the rotation.

[0061] Also, the driving gear 27 and the driven gear 28 are directlylinked, so that the driving force can be transmitted more reliably.However, if the stroke Y of the arm 30 in the thickness direction is tobe increased, the radius of the driving gear 27 needs to be increased,which may take up more space in the storage part 15. In such cases, asshown in FIGS. 7(a) and 7(b), it is possible to provide a large strokewithout increasing the radius of the driving gear 27 by attachingintermediate gears to the arm 30.

[0062]FIG. 7(a) shows yet another example of a paper sheet managingdevice 2 according to the present invention, while FIG. 7(b) shows theconstruction of the sheet supply means 19 that has been extracted fromFIG. 7(a). This sheet supply means 19 also includes a pick up roller 21and a drive shaft 22 for driving the pick up roller 21. The sheet supplymeans 19 of present example also includes three power transmittingmechanisms 44 a, 44 b, and 44 c for transmitting the driving force fromthe drive shaft 22 to the pick up roller 21. Out of these powertransmitting mechanisms 44 a, 44 b, and 44 c the power transmittingmechanisms 44 a and 44 b are arranged at both ends 21 e of the pick uproller 21, while the remaining power transmitting mechanism 44 c isdisposed in the middle or intermediate part of the pick up roller 21,with these three power transmitting mechanisms supporting the pick uproller 21 from the drive shaft 22 and transmitting the driving force.

[0063] In this paper sheet managing device 2 also, each of the powertransmitting mechanisms have the same construction, so that the powertransmitting mechanism 44 a arranged on the right side when looking fromthe sheet feeding side is described as a representative example. In thesame way as the above case, the power transmitting mechanism 44 aconnects the drive shaft 22 and the pick up roller 21 and includes anarm 30 that swings about the drive shaft 22 and a gear train 25 thatlinks the drive shaft 22 and the pick up roller 21. The gear train 25has two intermediate gears 29 a and 29 b disposed between the drivinggear 27 and the driven gear 28, with these intermediate gears 29 a and29 b being attached to the arm 30. This means that the axis 32 aboutwith the arm 30 swings and the rotational axis 21 a of the pick uproller 21 are linked by the driving gear 27, the driven gear 28 and thetwo intermediate gear 29 a and 29 b, a total of four gears (an evennumber of gears). On a pick up roller-side 30 b of the arm 30, the powertransmitting mechanism 44 a is provided with a frictional forcegenerating means 45, which uses felt or the like and generates africtional force when the driven gear 28 rotates. A frictional loadgenerating means can also be provided between the arm 30 and theintermediate gears 29 a or 29 b. The power transmitting mechanism 44 aalso operates in the same way as the power transmitting mechanisms 42 aand 42 b described above, so that when the drive shaft 22 is driven inthe anticlockwise direction, the intermediate gears 29 a and 29 brespectively rotate in the clockwise direction and the anticlockwisedirection, so that the pick up roller 21 rotates in the clockwisedirection and feeds a paper sheet. At this point, the frictional loadgenerating means 45 generates a moment that swings the arm 30 in theanticlockwise direction, which is the same direction as the rotation ofthe drive shaft 22, so that the pick up roller 21 moves towards andcomes into contact with the thermal sheets 3. When the pick up roller 21comes into contact, a pressing force acts and a thermal sheet 3 can bereliably fed.

[0064] In this way, the power transmitting mechanism 44 a of the presentexample has two intermediate gears 29 a and 29 b in the gear train 25,so that the distance between the drive shaft 22 and the pick up roller21 can be widened without increasing the radii of the driving gear 27and the driven gear 28. Accordingly, the stroke of the pick up roller 21in the thickness direction can be increased without sacrificing space inthe thickness direction in the storage part 15. Since the stroke can beincreased by providing a plurality of intermediate gears, there is noneed to increase the radii of the intermediate gears also. When theconstruction described in this example is used, space in the storagepart 15 hardly be taken up by the intermediate gears, so that there isno need to provide the intermediate gears outside the storage part 15.However, it is preferable for the direction in which the arm 30 swingsto match the rotational direction of the drive shaft 22, with it alsobeing necessary for the pick up roller 21 to rotate in the sheet feedingdirection, which is to say, in the clockwise direction. In order tomaintain these rotational directions, it is necessary to provide two oranother even number of intermediate gears 29. The driving gear 27 andthe driven gear 28 are provided along with an even number ofintermediate gears, so that if the swing direction of the arm 30 is tobe oriented towards the thermal sheets 3, the number of gears that linkthe center 32 and the rotational axis 21 a of the pick up roller 21inevitably has to be an even number.

[0065] In the space in the storage part 15 between the side walls 17 and18, the sheet supply means 19 of the present example is also providedwith a support bearing 23 that supports the intermediate part of thedrive shaft 22. This bearing 23 is C-shaped and has two front tips 23 a,each of which supports a midpoint of the drive shaft 22. This means thatin the present example, the drive shaft 22 is supported at twointermediate points in addition to the two points at the side walls 17and 18, and so is supported at a total of four points, which makes itextremely difficult for warping and bending to occur. As a result, evenif an even finer drive shaft 22 is used, warping and bending can besufficiently prevented and paper sheets can be fed accurately andreliably. In particular, when large sheets are used in a slimlineprinter, such as when printing is performed on A6-sized or largersheets, the length of the drive shaft 22 is increased, which makes iteasy for warping and bending to occur. Accordingly, it is preferable toprevent warping and bending by supporting the shaft in the middle asdescribed above.

[0066] In addition, in the present example the pick up roller 21 issupported and is driven not just at the two ends but also in the middleby the power transmitting mechanism 44 c. Accordingly compared to thecase where the pick up roller 21 is only supported at both ends, it ismore difficult for warping and bending to occur, the pick up roller 21can be made even smaller, and the space in the paper storage part(storage part) 15 can be used more effectively. By providing a powertransmitting mechanism in the middle of the pick up roller 21 androtationally driving the pick up roller 21 using this mechanism also, itis possible to prevent twisting of the pick up roller 21 and deviationsin the paper feeding direction due to skewing of the thermal sheets 3,so that more reliable paper feeding operations can be made.Additionally, when the pick up roller 21 is rotated at one or moreintermediate parts in addition to the two ends, it is even moreimportant to maintain the rotational phase of such positions. To do so,gears, which differ from rollers and pulleys in that there is nopossibility of slipping, are used as the driving force transmittingmechanisms. In addition, by providing irregularly shaped parts, such asparts cut in D shapes, in the drive shaft 22, the gears can be preventedfrom slipping on the drive shaft 22, which also prevent phase shiftsfrom occurring for the gears.

[0067] In a slimline printer that is compatible with large paper, boththe drive shaft 22 and the pick up roller 21 need to be extended, sothat it is extremely effective to support the middle of the pick uproller 21 as in the present example so as to prevent bending andwarping. Also, in the present example, the intermediate gears 29 aresupported by the arms 30, so that these intermediate gears 29 can beprovided without sacrificing the space 15 for holding thermal sheets 3.Accordingly, a plurality of power transmitting mechanisms can beprovided with a suitable pitch in the longitudinal direction of the pickup roller 21. Also, a gear train 25 does not need to be provided onevery arm 30 that supports the pick up roller 21, and bending andwarping can be suppressed by providing a plurality of arms 30 withoutgear trains.

[0068] However, to increase the reliability with which paper (thermalsheets) is fed with the proper orientation, it is preferable for a geartrain 25 to be provided on every arm 30 and to drive the pick up roller21. In the sheet supply means 19 of the present embodiment, the rotationof the pick up roller 21 presses the pick up roller 21 onto the sheetsunder its own force, so that so long as the pick up roller 21 rotates, aforce pressing the pick up roller 21 on the paper is generated.Accordingly, the pickup roller 21 presses the paper with an evenpressure at all of the positions where the pick up roller 21 contactsthe paper, so that paper can be reliably supplied in a slim space withinthe printer, though if the rotation of the pick up roller 21 becomesunbalanced, the force pressing the pick up roller 21 on the paper alsobecomes unbalanced, which can cause deviation in the paper feedingdirection.

[0069] When one or a plurality of power transmitting mechanisms areprovided in the intermediate parts of the pick up roller 21, shaft 21 aof corresponding parts of the pick up roller 21 may be exposed, so thatthe part of the pick up roller 21 that contacts the paper is dividedinto a plurality of parts. In the illustrated example, two roller parts21 b and 21 c are provided. If the platen roller 7 is split up, it isnot possible to evenly apply pressure to the paper sheet, which causesdeterioration in print quality. For the pick up roller 21 however, thereis no need to apply pressure to an entire paper sheet, and it issufficient to apply an even force to sheets within the limit for feedingthe paper with the correct orientation. This means that dividing thepick up roller does not cause problems.

[0070] As described above, the paper sheet managing device 2 uses asheet supply means 19 where the pick up roller 21 is rotationally drivenvia power transmitting mechanisms that include the arms 30, so that thepick up roller 21 can be pressed against the thermal sheets 3 by itselfand feed paper one sheet at a time without using a bottom plate, aspring, or the like. By having the arms 30 swing, sufficient space canbe provided in the housing of a slimline printer as the storage part 15,so that thermal sheets 3 can be fed one at a time right up to the finalsheet. Since the pick up roller 21 is pressed by a reactionary force tothe force that feeds sheets, by setting the sheet transporting speed ofa mechanism, such as the platen roller 7, that determines the sheettransporting speed near the thermal head 6 higher than the feeding speedof the pick up roller 21, the load of the pick up roller 21 can beeasily eradicated, and the load of a motor for sheet feeding operationscan be reduced. For these reasons, the sheet supply means 19 of thepresent example is suited to the realization of a slimline, compactprinter 1.

[0071] In addition, while it is necessary to use a pick up roller 21with a small diameter relative to its length in order to realize theprinter 1, the drop in the contact area of the pick up roller 21 can besufficiently compensated for by ensuring that the effective length ofthe pick up roller 21 is sufficiently long. On the other hand, problemssuch as bending and warping due to such increases in the effectivelength are reduced by supporting both ends 21 e of the pick up roller 21with the power transmitting mechanisms described above. The pick uproller 21 is subjected to a pressing force that is generated by itselfwhen it rotates, so that by synchronizing the rotation it is easy toensure that the pressing force is even and protect the constructionagainst problems such as bending and warping. Accordingly, sheet can bereliably fed with no deviation using a flexible pick up roller 21 thathas a small diameter.

[0072] This means that with the sheet feed means of the presentinvention, the internal space of a slimline printer or paper sheetmanaging device can be effectively used, and thermal sheets 3 can bereliably fed by a pick up roller 21 that is flexible due to its smalldiameter. Accordingly, the present invention realizes a paper sheetmanaging device that is suited to extremely slimline card-type ornote-type printer in the field of independent apparatus, so that it ispossible to produce printers whose product image completely differs fromconventional printers in terms of portability and compactness. A printeraccording to the present invention can be produced in an extremelyslimline form, which makes it easy to incorporate the printer into avariety of appliances, such as a mobile appliance like a mobile phone orPDA, a desktop or notebook computer, a cash register, or a carnavigation system. It is also possible to provide a printer that isattached to such appliances as an accessory.

[0073] It should be noted that as described above, it is preferable forthe thermal sheets 3 to be set in the storage part 15 inside using asheet cassette or sheet cartridge 9 provided with a tongue, though aplurality of paper sheets may be set directly in the storage part 15. Itis also possible for the printer to be constructed so that a papercartridge is detachably inserted into the printer main body. While anexample of a slimline portable printer has been described above, thepresent invention is not limited to the small paper sizes such as A6(105 mm by 148 mm) or below mentioned above, and can be adapted in apaper sheet managing device that uses sheets that are A5 size (148 mm by210 mm) or larger. The present invention is also not limited to devicesthat simply output print information received from a host, and may beapplied to a great variety of recording apparatuses equipped withfunctions such as facsimile, photocopying, and camera functions.

[0074] Also, while a thermal printer is described as an example, thepresent invention is adapted to an ink jet printer or laser printer.Thermal printers do not require consumables such as ink or toner, andthe printing mechanism can be made extremely small compared to othertypes of printer, which means that thermal printing is suitable for aslimline printer. Accordingly, the thermal printer is suited to slimlineprinters with a thickness of around 5 mm according to the presentinvention. An example of a platen roller is also given above, thoughwith the slimline printer 1, there is the possibility ofstrength-related problems occurring if a platen roller with a smalldiameter is used. In this case, it is effective to improve rigidity byreplacing the platen roller with a platen that does not rotate and toprovide a paper transporting roller (discharge mechanism) as a papertransporting means at a position for pulling thermal sheets that havebeen printed upon the thermal head 6.

[0075] Also, since the paper sheet managing device 2 of the presentinvention can be made extremely slim and thin, it is also possible tostack a plurality of such paper sheet managing devices 2 so as provide acompact multi-tray apparatus in which sheets of various types can beset. An example of such is shown in FIG. 8. In the illustratedmulti-tray-type paper sheet managing device 2, two storage parts 15 aand 15 b are provided one on top of the other, with sheet supply means19 a and 19 b being respectively provided in these storage parts 15 aand 15 b. The sheet supply means 19 a and 19 b are each equipped withthe pick up roller 21, the drive shaft 22 and the power transmittingmechanisms 42 described above. By selecting either the sheet supplymeans 19 a or the sheet supply means 19 b, one of the paper sheet 3 aand 3 b that are stored in the storage parts 15 a and 15 b is selected,and one sheet at a time can be separated by the front walls 16 a and 16b and outputted from the same position.

[0076] While the paper sheet managing device 2 has a two-levelconstruction, a multi-tray with three or more levels are also possible.By storing sheet of different sizes, different quality paper sheet,sheet of different formats etc. in the respective storage part in thismulti-tray-type paper sheet managing device 2, the desired sheet can beselected by merely selecting which sheet supply means 19 is to bedriven, with sheets of the selected paper being fed to the printingmechanism 4 and printed upon. While it is also possible for theplurality of storage parts to be arranged on a single plane, the sheetfeed means of the present invention has a slimline construction, so thata plurality of trays can be arranged in the same thickness as a singleconventional tray. Accordingly, by using the present invention, aprinter that can handle a plurality of types of paper can be providedwithout increasing the thickness of the part that stores the paper.

Industrial Applicability

[0077] As described above, the paper sheet managing device of thepresent invention and the recording system that uses the paper sheetmanaging device can reliably supply paper in the storage part one sheetat a time to a printing head using a simple construction that uses apick up roller with a long effective length and small diameter.Accordingly, an extremely slimline and thin paper sheet managing devicecan be provided, and a card-type or notebook-type recording system withan overall slimline construction that is suited to use with a mobilephone, PDA, etc can also be provided. The present invention is suited toadoption in a wide range of apparatuses that handle sheet, and byarranging storage parts on a plurality of levels, for example, a compactmulti-tray apparatus can be provided.

1. (Amended) A paper sheet managing device including a storage part for storing paper sheets and sheet supply means for supplying a paper sheet from the storage part, the sheet supply means comprising: a pick up roller extending in a sheet width direction orthogonal to a sheet feeding direction; a drive shaft extending parallel to the pick up roller and rotationally driving the pick up roller; and a plurality of power transmitting means for transmitting a power from the drive shaft to the pick up roller, the plurality of power transmitting means being disposed at at least both ends of the pick up roller and each of the plurality of power transmitting means being comprising: a gear train that links the drive shaft and the pick up roller; an arm that swings about an axis of a gear in the gear train, to a front end of the arm, a rotational axis of the pick up roller being attached so as to an even number of gears that form at least part of the gear train links between the axis about which the arm swings and the rotational axis of the pick up roller; and frictional force generating means for generating friction force in accordance with rotation between the arm and either the even number of gears or the rotational axis of the pick up roller, wherein engaging parts of the driving shaft and the pick up roller that are engaged to the gears are irregularly shaped shaft parts and the pick up roller is flexible.
 2. A paper sheet managing device according to claim 1, wherein the pick up roller is sized so that the pick up roller contacts with at least 50% of a width of the paper sheets set in the storage part.
 3. A paper sheet managing device according to claim 1, wherein the gear train includes a driving gear that is driven by the drive shaft, a driven gear that drives the pick up roller, and at least one intermediate gear that links the driving gear and the driven gear.
 4. A paper sheet managing device according to claim 3, wherein the plurality of power transmitting means are disposed on outside of the storage part, the arm swings about an axis of the intermediate gear, and the even numbers of gears are the intermediate gear and the driven gear.
 5. A paper sheet managing device according to claim 3, wherein the plurality of power transmitting means are disposed on inside of the storage part, the arm swings about a center of the drive shaft, and the at least one intermediate gear includes an even number of gears that are supported by the arm.
 6. A paper sheet managing device according to claim 1, further comprising a shaft bearing that supports the drive shaft at at least one position inside the storage part.
 7. A paper sheet managing device according to claim 1, further comprising a plurality of storage parts and a plurality of sheet supply means for supplying the paper sheet from the plurality of storage parts respectively.
 8. A paper sheet managing device according to claim 7, wherein the plurality of storage parts are stacked on multiple levels.
 9. A paper sheet managing device according to claim 1, wherein in the storage part, a sheet cassette for storing a plurality of paper sheets and having a tongue-like protruding underlay is set.
 10. (Amended) A recording system including a print head, sheet feed means for feeding paper sheet under controlling a feeding speed for printing by the print head, a storage part for storing paper sheets and sheet supply means for supplying the paper sheet from the storage part to the sheet feed means, the sheet supply means comprising: a pick up roller extending in a sheet width direction orthogonal to a sheet feeding direction; a drive shaft extending parallel to the pick up roller and rotationally driving the pick up roller; and a plurality of power transmitting means for transmitting a power from the drive shaft to the pick up roller, the plurality of power transmitting means being disposed at least both ends of the pick up roller and each of the plurality of power transmitting means being comprising: a gear train that links the drive shaft and the pick up roller; an arm that swings about an axis of a gear in the gear train, to a front end of the arm, a rotational axis of the pick up roller being attached so as to an even number of gears that form at least part of the gear train links between the axis about which the arm swings and the rotational axis of the pick up roller; and frictional force generating means for generating friction force in accordance with rotation between the arm and either the even number of gears or the rotational axis of the pick up roller, wherein engaging parts of the driving shaft and the pick up roller that are engaged to the gears are irregularly shaped shaft parts and the pick up roller is flexible.
 11. A recording system according to claim 10, wherein the pick up roller is sized so that the pick up roller contacts with at least 50% of a width of the paper sheets set in the storage part.
 12. A recording system according to claim 10, wherein a feeding speed of the sheet feed means is faster than a feeding speed of the sheet supply means.
 13. A recording system according to claim 10, wherein the gear train includes a driving gear that is driven by the drive shaft, a driven gear that drives the pick up roller, and at least one intermediate gear that links the driving gear and the driven gear.
 14. A recording system according to claim 13, wherein the plurality of power transmitting means are disposed on outside of the storage part, the arm swings about an axis of the intermediate gear, and the even numbers of gears are the intermediate gear and the driven gear.
 15. A recording system according to claim 13, wherein the plurality of power transmitting means are disposed on inside of the storage part, the arm swings about a center of the drive shaft, and the at least one intermediate gear includes an even number of gears that are supported by the arm.
 16. A recording system according to claim 10, further comprising a shaft bearing that supports the drive shaft at at least one position inside the storage part.
 17. A recording system according to claim 10, further comprising a plurality of storage parts and a plurality of sheet supply means for supplying the paper sheet from the plurality of storage parts respectively.
 18. A recording system according to claim 17, wherein the plurality of storage parts are stacked on multiple levels.
 19. A recording apparatus according to claim 10, wherein in the storage part, a sheet cassette for storing a plurality of paper sheets and having a tongue-like protruding underlay is set. 